Development and validation of a comprehensive tool for measuring multidimensional peritraumatic experience.

Despite available instruments to assess peritraumatic reactions - such as tonic immobility, dissociation, and panic reactions - content overlap remains an issue. To date, no comprehensive tool integrates these dimensions into a single valid instrument. This study consolidates items from various sources to create a standalone solution, employing both qualitative and quantitative approaches. At several stages, experts examined potential content overlaps and redundancies in item components, supported by psychometric assessments using exploratory structural equation models and confirmatory factor analysis. The 29-item instrument exhibits robust configural and metric properties, including unique items per factor, high reliability, absence of content redundancy, and convergent and discriminant factorial validity. The provisionally named Peritraumatic Response Questionnaire (PTRQ) seems suitable for use in epidemiological studies in its current state. Further refinement may enhance its comprehensiveness and suitability for broader applications. Thus, we propose this instrument for assessing peritraumatic experiences, with potential for future enhancement by continued research.